FIG. 1 shows a relay node (RN) 120, a user equipment (UE) 131 and a user equipment (UE) 132 within an area of a base station (eNodeB: eNB) 110 in a wireless communication system 100. The relay node 120 may deliver data received from the base station 110 to the user equipment 132 within a relay node area and may deliver data received from the user equipment 132 within the relay node area to the base station 110. The relay node 120 may extend a fast data rate area, raise communication quality on a cell edge, and support a communication to be provided to an inside of a building or an area out of a base station service area. Referring to FIG. 1, such a user equipment (hereinafter named Macro-UE) directly receiving a service from the base station as a user equipment 131 and such a user equipment (hereinafter named Relay-UE) receiving a service from the relay node 120 as a user equipment 132 may coexist.
FIG. 2 shows links among a base station, a relay node and a user equipment. The relay node may be connected with the base station via an interface Un by wireless. And, a radio link between the base station and the relay node is called a backhaul link. And, a link from the base station to the relay node is called a backhaul downlink. Moreover, a link from the relay node to the base station is called a backhaul uplink. The relay node may be connected to a user equipment via an interface Uu by wireless and a radio link between the relay node and the user equipment is called an access link. A link from the relay node to the user equipment is called an access downlink and a link from the user equipment to the relay node is called an access uplink. If a backhaul link operates on a same frequency band of an access link, it can be called ‘in-band’. If a backhaul link and an access link operate on different frequency bands, respectively, it can be called ‘out-band’.
Via a backhaul link from a relay node to a base station, it may be necessary to transmit such physical layer control information as scheduling request (SR), downlink channel measurement information, acknowledgement/negative-acknowledgement (ACK/NACK) for downlink data transmission and the like. Yet, a method of transmitting the above-mentioned backhaul uplink physical layer control information has not been determined in detail.